The U.S. stock market suffered its worst day in a week after Intel Corp.'s earnings and the prospect of banks' growing loan losses prompted concern profit forecasts will be reduced in the weeks ahead.

Intel sparked the biggest tumble in semiconductor shares in almost five months after saying increased competition forced it to cut computer chip prices. Citigroup Inc. and JPMorgan Chase & Co. led 86 of 92 financial firms in the Standard & Poor's 500 Index lower following Bear Stearns Cos.' disclosure that investors in two hedge funds were wiped out by bad bets on subprime mortgages.

The S&P 500 lost 3.2, or 0.2 percent, to 1546.17. The Dow average dropped 53.33, or 0.4 percent, to 13,918.22. The Nasdaq Composite Index slid 12.8, or 0.5 percent, to 2699.49.

Key themes today were disappointment over earnings, Bernanke and the Fed's growth forecast for the U.S. economy (cut downwards from an earlier forecast), and worries over the fallout in the subprime mortgage bond market and the cratering ABX indices.

On top of all this, we've got everyone paying attention to higher energy prices as the price of crude oil creeps back towards $80. We'll let T. Boone Pickens take it from here, as he describes his forecast for higher oil prices to CNBC.